A serum facted by newborn calf serum.

An intraperitoneal injection of newborn calf serum (NBCS) into CRF Swiss mice causes an inflammatory reaction characterized by an increase in the number of macrophages in the peritoneal cavity and a concomitant monocytosis. The serum of such mice contains a monocytosis-inducing factor, as demonstrated by the intravenous injection of serum collected 18 (CalS18) and 24 hr (CalS24) after the intraperitoneal injection of NBCS. Serum from normal untreated mice, from mice given an intraperitoneal injection of sterile pyrogen-free saline, which does not cause an inflammatory reaction, or from mice 72 hr after an intraperitoneal injection of NBCS, when the inflammatory reaction has subsided, does not cause a monocytosis in test mice. Intravenous injection of CalS18 causes not only a monocytosis but also an increase in the number of promonocytes and bone marrow monocytes, suggesting an increased in the number of promonocytes and bone marrow monocytes, suggesting an increased production of monocytes. The effect of CalS18, CalS24 and CalS18 filtrate is specific for the mononuclear phagocytes, since only non-significant increases in the numbers of lymphocytes and granulocytes were observed. The active factor in CalS18 was shown to be different from the monocytosis-inducing factor present in NBCS. The monocytosis-inducing factor in CalS18 passes through an ultrafiltration membrane with an exclusion limit of 50,000 Daltons, so that the molecular weight must be below this value.     

A SERUM FACTOR INDUCING MONOCYTOSIS DURING AN ACUTE INFLAMMATORY REACTION CAUSED BY NEWBORN CALF SERUM

An intraperitoneal injection of newborn calf serum (NBCS) into CRF Swiss mice causes an inflammatory reaction characterized by an increase in the number of macrophages in the peritoneal cavity and a concomitant monocytosis. The serum of such mice contains a monocytosis-inducing factor, as demonstrated by the intravenous injection of serum collected 18 (CalS 18) and 24 hr (CalS24) after the intraperitoneal injection of NBCS. Serum from normal untreated mice, from mice given an intraperitoneal injection of sterile pyrogen-free saline, which does not cause an inflammatory reaction, or from mice 72 hr after an intraperitoneal injection of NBCS, when the inflammatory reaction has subsided, does not cause a monocytosis in test mice. Intravenous injection of CalS 18 causes not only a monocytosis but also an increase in the number of promonocytes and bone marrow monocytes, suggesting an increased production of monocytes. The effect of CalS 18, CalS24 and CalS 18 filtrate is specific for the mononuclear phagocytes, since only non-significant increases in the numbers of lymphocytes and granulocytes were observed. The active factor in CalS 18 was shown to be different from the monocytosis-inducing factor present in NBCS. The monocytosis-inducing factor in CalS 18 passes through an ultrafiltration membrane with an exclusion limit of 50,000 Daltons, so that the molecular weight must be below this value.     

苜蓿丫纹夜蛾核型多角体病毒囊膜内核衣壳排列图式的电镜观察

核型多角体病毒有单核衣壳包埋型和多核衣壳包埋型之分,单核衣壳包埋型是在一个病毒囊膜内只包含一个核衣壳,而多核衣壳包埋型的特点是在一个病毒囊膜内包含有２个以上的核衣壳,由于多个核衣壳成束地被包装在同一个病毒囊膜内,又称病毒束［１,２］。Ｈｕｎｔｅｒ等表明在干果斑螟核型多角体病毒中,病毒囊膜内包含２～２３个核衣壳［３］。Ｆｒａｓｅｒ将苜蓿丫纹夜蛾核型多角体病毒接种于秋粘虫细胞系,超薄切片电镜观察,病毒囊膜内包含的核衣壳数变动于２～１７粒,但未研究其核衣壳在病毒囊膜内的排列结构［４］。本研究用苜蓿丫纹…     

The competitive ability of stem cells from mice with Hertwig's anemia

Mice homozygous for the gene, an, have a macrocytic, normochromic anemia. In this report, attempts have been made to cure Hertwig's anemia (an/an) by injecting genetically normal (+/+) stem cells. The anemia of unirradiated an/an mice was alleviated but not completely cured by injection of as many as 3 X 10(7) +/+ bone marrow cells. Lethal irradiation of the an/an recipients was necessary before injections of 10(7) +/+ marrow cells were effective in normalizing the blood parameters. The inability to achieve normal blood values without first destroying the host's own stem cells suggested that the indigenous an/an cells compete effectively with injected +/+ cells. This hypothesis was tested by injecting varying numbers of stem cells from C57BL/6J-+/+ mice, together with stem cells from either WBB6F1-an/an or, as controls, from their WBB6F1-+/+ littermates, into lethally irradiated hosts. The C57BL/6J and WBB6F1 mice have electrophoretically distinguishable hemoglobins. The an/an cells are able to compete in the repopulation of the host hematopoietic tissue as shown by the presence of WBB6F1 hemoglobin in the recipients. The cells from mice with Hertwig's anemia, however, do not compete as effectively as do the same number of cells from the +/+ littermates. These results indicate that the pluripotent hematopoietic stem cells of an/an mice are reduced in number, seeding capacity, or proliferative potential.     

Types of Systemic Reactions of Human Hemodynamics and Hemostasis to Multiple Occupational Migrations to the Polar Circle Regions

Effects of meridional migrations in shuttle from middle latitudes to regions beyond the Polar Circle, where an expedition and the organization of work shifts were being conducted, were studied. Three main types of systemic reactions of human hemodynamics and hemostasis were established. The first type was characterized by a moderate increase in the arterial blood pressure (BP) at the beginning of the shift with its subsequent normalization; by hypocoagulemia; and by an increase in the total phospholipid content, with a significant increase in the content of lysolecithins (an adaptive type). The second type was characterized by hypertension throughout the whole shift, by hypercoagulemia with significant changes in the phospholipid spectrum, and with a pronounced increase in the lysolecithin and cardiolipin fractions (a hypertensive type). The third type was characterized by a decrease in BP and an increase in heart rate (HR), by hypocoagulemia and an asthenic state associated with sleep disorders, and a decreased mental capacity (an asthenic type).     

The structure of the ostracode carapace

The carapace ultrastructure of three Recent [Heterocypris incongruens (Ramdohr), Cypridopsis uidua (Müller), and Conchoecia belgica Müller] and one Cretaceous ostracode species [Cypridea propunctata Sylvester-Bradley] has been studied by means of standard electron microscope techniques. The carapace is shown to be an organic structure divisible into an outer epicuticle, a median exocuticle and an inner endocuticle in the three cypridacean ostracodes examined. In Conchoecia belgica only an outer epicuticle and an inner endocuticle were observed, but this may be due to preservation. The chitin structure of the carapace of calcareous ostracodes is shown to be essentially an interlocking lattice, more coarsely developed in the exocuticle; layered (lamellar) chitin is only present in the selvage and in the connective tissue joining the valves at the hinge. The non-calcareous Conchoecia belgica possesses the layered chitin structure common to other crustaceans and to insects. The relationship of the carapace structure to that present in the decapod and insect exoskeleton is discussed. The technical problems met with during this study are considered in order to outline the difficulties associated with the study of organisms of this size.     

Adaptations to training at the individual anaerobic threshold

The individual anaerobic threshold (Th(an)) is the highest metabolic rate at which blood lactate concentrations can be maintained at a steady-state during prolonged exercise. The purpose of this study was to test the hypothesis that training at the Th(an) would cause a greater change in indicators of training adaptation than would training "around" the Th(an). Three groups of subjects were evaluated before, and again after 4 and 8 weeks of training: a control group, a group which trained continuously for 30 min at the Th(an) intensity (SS), and a group (NSS) which divided the 30 min of training into 7.5-min blocks at intensities which alternated between being below the Th(an) [Th(an) -30% of the difference between Th(an) and maximal oxygen consumption (VO2max)] and above the Th(an) (Th(an) +30% of the difference between Th(an) and VO2max). The VO2max increased significantly from 4.06 to 4.27 l.min-1 in SS and from 3.89 to 4.06 l.min-1 in NSS. The power output (W) at Th(an) increased from 70.5 to 79.8% VO2max in SS and from 71.1 to 80.7% VO2max in NSS. The magnitude of change in VO2max, W at Th(an), % VO2max at Th(an) and in exercise time to exhaustion at the pretraining Th(an) was similar in both trained groups. Vastus lateralis citrate synthase and 3-hydroxyacyl-CoA-dehydrogenase activities increased to the same extent in both trained groups. While all of these training-induced adaptations were statistically significant (P < 0.05), there were no significant changes in any of these variables for the control subjects.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cell wall-degrading enzymes produced by Penicillium oxalicum Curie et Thom

Penicillium oxalicum Curie et Thom produced an exo-polygalacturonase, an endo-polygalacturonase and an endo-pectate lyase. It also produced cellulase C_x, cellobiase, B-glucosidase, xylanase, galactanase and arabinanase in culture and in infected yam tissues.The exo-polygalacturonase was unstable. It has a molecular weight of about 38 000 daltons. The endopolygalacturonase and endo-pectate lyase had an optimal pH of 5.0 and 8.5 and an isoelectric point (pI) at pH 3.6 and 4.9 respectively. Molecular weights of both enzymes were about 28 500 and 30 000 daltons respectively. The end products of the reaction were oligogalacturonides and revealed that cellulose was degraded to glucose, with cellobiose as an intermediate product. The end products of the degradation of hemicelluloses were xylose, galactose and arabinose.     

The pro-sequence domain of streptopain directs the folding of the mature enzyme

The cysteine endopeptidase streptopain, an extracellular enzyme from pathogenic Streptococcus pyogenes, is synthesized as a precursor containing an NH2-terminal pro-sequence. The pro-sequence of streptopain was expressed in Escherichia coli and subjected to structural and functional investigation. Heat-induced denaturation of the pro-sequence studied using circular dichroism spectroscopy revealed that it forms a compact structure and represents an independently folded domain. The isolated pro-sequence exhibits high affinity towards mature streptopain and associates with its cognate enzyme by forming an equimolar complex. Refolding of denatured streptopain in the presence of pro-sequence in vitro facilitated recovery of active enzyme. Expression of the mature streptopain in E. coli either alone, or in trans with its pro-sequence as an independent polypeptide, led to the formation of insoluble protein aggregates or functionally active enzyme, respectively. These results demonstrate that the pro-sequence domain acts as an intramolecular chaperone that directs the correct folding of the mature streptopain.     

Hypoglycemic Activity of Endotoxin II. Mechanism of the Phenomenon in BCG-infected Mice

The mechanism of the hypoglycemic activity of endotoxin in hyperreactive BCG mice was investigated. The mechanism was found to be an inhibition of the synthesis of glucose from noncarbohydrate sources. The possibilities of an induced hypermetabolic state and an induced release of insulin in response to endotoxin as causes for the hypoglycemic response were essentially ruled out. In addition, no clear-cut evidence of an insulin-like action by endotoxin was found in the in vivo setting.     

The process of dissolving apolipoprotein A-I in an aqueous buffer

Human plasma apolipoprotein A-I (apoA-I) has been studied in an aqueous solution by the techniques of high performance liquid chromatography (HPLC), circular dichroic spectroscopy, and sedimentation equilibrium ultracentrifugation. The results indicate that an oligomer is formed as an intermediate step of dissolving lysophilized apoA-I. The process of further dissolution of this oligomer is an irreversible, temperature-dependent dissociation. The half-life of this intermediate oligomer is 3 min at 37 degrees C and 80 h at 30 degrees C. The completely dissolved apoA-I in an aqueous buffer self-associates with conformational alteration. The self-association equilibrium is too rapid to be demonstrated by HPLC.     

哺乳动物季节性繁殖的神经内分泌调节机制

动物的季节性繁殖, 是指其繁殖活动从静止到复苏的一个年周期性循环。研究显示, kisspeptin和RFRP对繁殖的季节性变化具有重要作用。非繁殖期最显著的特点是雌激素对GnRH分泌的负反馈效应的增加, 而雌激素的这种效应是由kisspeptin神经元传导的。因此, kisspeptin是影响繁殖活动的一个重要因子。RFRP的表达依赖于褪黑激素的分泌并呈现出季节性变化, 在非繁殖期对繁殖活动的抑制作用非常明显。此外, 甲状腺激素在繁殖期的终止上发挥着至关重要的作用, 而多巴胺能神经元A14/A15也促进了雌激素负反馈效应的季节性变化。这些神经元系统通过协同作用一起调节了生殖功能随光周期的季节性转变。文章对繁殖的季节性和这4个神经内分泌系统之间的关系进行了系统的阐述。     

Human Discrimination of the Angular Velocity of the Vertical Movement of an Acoustic Image in Opposite Directions

The discrimination of the angular velocity of ventrodorsal and dorsoventral movement of an acoustic image was studied in nine test subjects. The experiments were performed using an apparent movement produced by consecutive activation of loudspeakers located along an arc in the vertical plane. The differential thresholds were measured by the minimum increment method. As the velocity of an acoustic image movement in opposite directions increased, the values of its mean absolute differential thresholds increased monotonically. Regression lines plotted by linear approximation of these values did not differ significantly.     

西安市生态环境及城市发展质量评估

良好的生态环境是推动城市高质量发展的重要基础,决定了城市建设水平与人居环境质量。以西安市为研究区,计算遥感生态指数(RSEI)评估城市生态环境状况;构建城市高质量发展评价指标体系,使用全排列多边形图示法评估城市发展质量;再运用耦合协调度模型分析两者耦合协调度的时间变化趋势。结果表明: 西安市城市生态状况呈南高北低的格局,2010—2020年RSEI整体呈上升趋势,但城内六区的RSEI一直在降低,周边区县的RSEI基本保持不变或有所提升;西安市城市发展质量有所提升,城市发展质量等级为较低级别,城市发展3个子系统的质量提升具有不均衡性,提升幅度为生态子系统>经济子系统>社会子系统;西安市两类指数的耦合协调度提高,协调水平从勉强协调提升为初级协调。     

Aggregation kinetics of extended porphyrin and cyanine dye assemblies

The kinetics of J-aggregate formation has been studied for two chromophores, tetrakis-4-sulfonatophenylporphine in an acid medium and pseudoisocyanine on a polyvinylsulfonate template. The assembly processes differ both in their sensitivity to initiation protocols and in the reaction profiles they produce. The porphyrin's assembly kinetics, for example, displays an induction period unlike that of the cyanine dye. Two kinetic models are presented. For the porphyrin, an autocatalytic pathway in which the formation of an aggregation nucleus is rate-determining appears to be applicable; for the pseudoisocyanine dye, an equation derived for diffusion-limited aggregation of a fractal object satisfactorily fits the data. These models are shown to be useful for the analysis of kinetic data obtained for several biologically important aggregation processes.     

Characteristics of molecular hydrogen and CH* radicals in a methane plasma in a magnetically enhanced capacitive RF discharge

The parameters of a methane-containing plasma in an asymmetric RF capacitive discharge in an external magnetic field were studied using optical emission spectroscopy. The power deposited in the discharge was 90 W and the gas pressure and magnetic field were varied in the ranges 1–5 Pa and 50–200 G, respectively. The vibrational and rotational temperatures of hydrogen molecules and CH* radicals were measured as functions of the magnetic field and methane pressure. The ratio between the densities of atomic and molecular hydrogen was estimated. The processes responsible for the excitation of molecular hydrogen and CH* radicals in a methane-containing plasma in an RF capacitive discharge are analyzed.